Pleioplectron crystallae, Hegg & Morgan-Richards & Trewick, 2019

Hegg, Danilo, Morgan-Richards, Mary & Trewick, Steven A., 2019, Diversity and distribution of Pleioplectron Hutton cave wētā (Orthoptera: Rhaphidophoridae: Macropathinae), with the synonymy of Weta Chopard and the description of seven new species, European Journal of Taxonomy 577, pp. 1-46 : 34-37

Pleioplectron crystallae sp. nov.

urn:lsid:zoobank.org:act:0C869BE1-87F8-45AE-A3B7-120B11DE9FBD

Figs 2 A–B, 4C–D, 6J, 7I, 9J–L, 11J–L, 12B, 15E–F, 18I

Diagnosis

A small cave wētā from the northwestern regions of the South Island of New Zealand, found predominantly near the tree line and in sub-alpine habitats, on the forest floor or on tree trunks, where it feeds on Racomitrium Brid. moss and occasionally on lichens. Unmistakable in its looks, this striking species stands out for its four or five pairs of very long, articulated spines on the hind tibiae, the chevron pattern on its back and a colour that varies from military green to brown and reddish brown. Because of its small size, the long spines on the hind tibiae and its preference for moss, it could be mistaken for Maotoweta virescens Johns & Cook, 2013 , although it is larger, never bright green and the spines on the hind tibiae do look different when examined under the microscope.

Etymology

Named for Crystal Brindle, hut warden at Gouland Downs when the species was first discovered.

Material examined (see also Table 10 in Supplementary Material)

Holotype

NEW ZEALAND • ♂, adult; Nelson (NN), Heaphy Track, Gouland Downs, Cave Brook ; 40.89240° S, 172.35540° E; 600 m a.s.l.; 4 Feb. 2018; Danilo Hegg leg.; moss on forest floor; night search + insect net; NMNZ AI.037490 (prev. MPN CW3994 ).

Paratype

NEW ZEALAND • ♀, adult; Nelson (NN), Mt Arthur Tablelands, Salisbury Lodge ; 41.18511° S, 172.64465° E; 1150 m a.s.l.; 8 Feb. 2017; Danilo Hegg leg.; moss on forest floor; night search + insect net; NMNZ AI.037491 (prev. MPN CW3941 ) .

Other material

NEW ZEALAND – Nelson (NN) • 1 ♀; Mt Owen, Blue Creek ; 41.51241° S, 172.56223° E; 1100 m a.s.l.; 10 Jan. 2019; D. Hegg leg.; on tree trunk; night search + insect net; MPN CW4267 • 2 ♂♂; Mt Owen, Branch Creek Hut; 41.52465° S, 172.51128° E; 920 m a.s.l.; 11 Jan. 2019; D. Hegg leg.; on tree trunk; night search + insect net; MPN CW4270 , CW4271 • 3 ♂♂; same collection data as for paratype; MPN CW3925 to CW3927 • 1 ♂; Mt Arthur Tablelands, Balloon Hut ; 41.16913° S, 172.62251° E; 1270 m a.s.l.; 7 Feb. 2018; D. Hegg leg.; in firewood shed; night search + insect net; MPN CW3944 • 1 ♂, 1 ♀; Heaphy Track, Gouland Downs, Cave Brook ; 40.89240° S 172.35540° E; 600 m a.s.l.; 20 Apr. 2016; D. Hegg leg.; moss on forest floor; night search + insect,net; MPN CW2997 , CW2998 • 1 ♂, 1 ♀; Heaphy Track, Gouland Downs, Cave Brook ; 40.89240° S 172.35540° E; 600 m a.s.l.; 26 Dec. 2016; D. Hegg leg.; moss on forest floor; night search + insect,net; MPN CW3894 , CW3900 • 1 ♂, 4 ♀♀; same collection data as for holotype; moss on forest floor and tree trunks; MPN CW3990 to CW3993 , CW3995 • 1 ♂; Heaphy Track, Perry Saddle ; 40.90029° S 172.40416° E; 900 m a.s.l.; 24 Dec. 2016; D. Hegg leg.; moss on forest floor; night search+ insect net; MPN, CW3618 . – Marlborough Sounds (SD) • 1 ♀; Mt Stokes ; 41.08747° S, 174.10983° E; 1000 m a.s.l.; 17 Nov. 2018; D. Hegg leg.; moss on forest floor; night search + insect net; MPN CW4152 .

Description

MEASUREMENTS. See Table 1.

HEAD. Frons mottled, a mix of dark brown and yellow patches, with sparse setae; vertex glabrous and of variegated colour. Eyes reddish brown and bulging. Fastigium reddish brown, with a white spot on

either side. Scapes and peduncles red with brown patches; antennae red, covered in fine setae. Maxillari and labial palpi mottled light brown, with fine tomentum ( Fig. 4 C–D).

THORAX. Pronotum mottled, red, red-brown, brown or military green; dark with pale bars next to anterior and posterior margins; covered in sparse, fine tomentum. Dorsal yellow median line generally pronounced. All margins are slightly rounded.

LEGS. Relatively short; hind femora generally shorter than body length. Hind tibiae up to 15% longer than body in females, up to 40% longer than body in males. Coxae and trochanters variegated. All legs red with inconspicuous brown patches or bands. Fore coxae with a pronounced lateral spine. Fore femora without linear spines above or below, but armed with one prolateral spine at apex. Fore tibiae armed below, generally with two linear spines on anterior edge, one linear spine on posterior edge. Fore tibiae armed with two long spines below (one prolateral and one retrolateral) and two short spines above (one prolateral and one retrolateral) at apex. Mid femora without linear spines above or below, but armed with one prolateral and one retrolateral spine at apex. Mid tibiae armed below, generally with two linear spines on anterior edge, one linear spine on posterior edge. Mid tibiae armed with two long spines below (one prolateral and one retrolateral) and two short spines above (one prolateral and one retrolateral) at apex. Hind femora armed below with up to five very small, retrolateral, linear spines but unarmed at apex. Hind tibiae with 13 to 22 linear spines of varying length above on both anterior and posterior edges, including four or five pairs of prominent, articulated spines, plainly visible to the naked eye ( Fig. 7I ). Hind tibiae with two superior subapical spines (one prolateral and one retrolateral), two superior apical spines (one prolateral and one retrolateral) and two inferior apical spines (one prolateral and one retrolateral). Superior subapical spines and inferior apical spines of approximately equal length, superior apical spines approximately twice as long. Hind tarsi with four segments, first and second segment with a pair of spines on distal end. First segment with 5–11 small dorsal, alternate spines. Second segment with 1–4 small dorsal, alternate spines. Second and fourth segments one third to one half of length of first segment; third segment one third of length of second and fourth segments.

ABDOMEN. Colour red, red-brown, brown or military green; covered in sparse, fine tomentum. Tergites adorned with a characteristic chevron or diamond pattern ( Figs 6J , 15 E–F). Dorsal yellow median line generally pronounced and well visible.

MALE TERMINALIA. Cerci long, pointed at apex, variegated, clothed in setae. Styli very short, not visible from above. Subgenital plate with an orange protuberance shaped like a blunt blade with lateral swellings at its tip ( Fig. 9J ). Suranal plate square ( Fig. 9K ).

FEMALE TERMINALIA. Subgenital plate with a single lobe ( Fig. 11J ). Ovipositor dark brown, tapering quickly near base, strongly recurved above at tip and on average about 80% as long as body. Upper valve smooth above, but lower valve with 6 to 9 strong teeth on ventral edge at apex ( Fig. 11 K–L). From above, terminalia appear to have a sharp point on last tergite ( Fig. 12B ).

Figures

Fig. 2. Phylogenetic relationships of Pleioplectron Hutton, 1896 cave wētā based on mtDNA sequence. A. Bayesian analysis using a mtDNA sequence alignment of 1429 bp spanning the majority of COI, with a minimum individual sequence length of 1330. Posterior probabilities are shown by nodes. B. Maximum Likelihood tree using PhyML with a COI alignment that contained sequences ranging from 483bp to 1429 bp, although the majority were>850 bp at the 3′ end of the gene. C. Map of New Zealand entomological (Crosby) regions. These codes are indicated in the Material examined section for each species.

Fig. 4. Head of cave wētā in the genus Pleioplectron Hutton, 1896 showing sexual dimorphism. A–B. P. simplex Hutton, 1896. A. Adult ♂, Hinewai Reserve, Banks Peninsula (MPN CW4118). B. Adult ♀, Helicopter Hill Track, Craigieburn (MPN CW3914). C–D. P. crystallae sp. nov. C. Adult ♂, Branch Creek Hut, Mt Owen (MPN CW4271). D. Adult ♀, Salisbury Lodge, Mt Arthur Tablelands (MPN CW3941). Scale bar = 5 mm.

Fig. 7. Left hind tibia of cave wētā in the genus Pleioplectron Hutton, 1896, dorsal view. A. P. simplex Hutton, 1896, adult ♀, Hinewai Reserve, Akaroa (MPN CW4114). B. P. hudsoni Hutton, 1896, adult ♂, Otaki Forks, Tararua Forest (MPN CW3890). C. P. thomsoni (Chopard, 1923) comb. nov., adult ♂, Claremont Bush Reserve, South Canterbury (MPN CW4115). D. P. triquetrum sp. nov., adult ♂, Hinau Track, Kaikōura (MPN CW3921). E. P. auratum sp. nov., adult ♂, Whites Beach, Rarangi (MPN CW4295). F. P. gubernator sp. nov., adult ♂, Lewis Pass (MPN CW4066). G. P. caudatum sp. nov., adult ♂, Moeraki River (MPN CW4239). H. P. flavicorne sp. nov., adult ♀, Brewster Hut Track, Haast Pass (MPN CW3896). I. P. crystallae sp. nov., adult ♂, Cave Brook, Gouland Downs (MPN CW3994). J. P. rodmorrisi sp. nov., adult ♂, Hodder River, Inland Kaikōura Range (MPN CW3819). Scale bar = 5 mm.

Fig. 6. Dorsal views of cave wētā in the genus Pleioplectron Hutton, 1896. A. P. simplex Hutton, 1896, adult ♀, Helicopter Hill Track, Craigieburn (MPN CW3914). B. P. thomsoni (Chopard, 1923) comb. nov., adult ♂, Claremont Bush, South Canterbury (MPN CW4115). C. P. gubernator sp. nov., adult ♀, Mt Arthur (MPN CW4056). D. P. triquetrum sp. nov., adult ♂, Hinau Track, Kaikōura (MPN CW3928). E. P. auratum sp. nov., adult ♂, Whites Beach, Rarangi (MPN CW4295). F. P. rodmorrisi sp nov., adult ♂, Hodder River, Inland Kaikōura Range (MPN CW3824). G. P. hudsoni Hutton, 1896, adult ♂, Karori, Wellington (MPN CW3564). H. P. caudatum sp. nov., adult ♂, Brewster Hut Track, Haast Pass (MPN CW4049). I. P. flavicorne sp nov., adult ♂, Brewster Hut Track, Haast Pass (MPN CW4055). J. P. crystallae sp nov., adult ♀, Cave Brook, Gouland Downs (MPN CW3991). Scale bar = 10 mm.

Fig. 15. Live Pleioplectron Hutton, 1896 in their natural environments. A. P. auratum sp. nov., adult ♂, Whites Beach, Rarangi. B. P. gubernator sp. nov., two adult ♂♂, Three Pointer, Gouland Downs, Heaphy Track. C. P. caudatum sp. nov., adult ♂, Blowfly Hut, Moeraki River, South Westland. D. P. flavicorne sp. nov., sub-adult ♀, Blowfly Hut, Moeraki River, South Westland. E–F. P. crystallae sp. nov. E. Adult ♂, Cave Brook, Gouland Downs, Kahurangi NP. F. Adult ♀ feeding on Racomitrium Brid. moss, Salisbury Lodge, Mt Arthur, Kahurangi NP.

Fig. 9. Adult male terminalia of cave wētā in the genus Pleioplectron Hutton, 1896. Left column: ventral view (subgenital plate); central column: dorsal view; right column: lateral view. A–C. P. gubernator sp. nov., Lewis Pass. A. MPN CW4063. B. MPN CW4067 C. MPN CW4059. D–F. P. caudatum sp. nov., Brewster Hut Track, Haast Pass (MPN CW4053). G–I. P. flavicorne sp. nov., Brewster Hut Track, Haast Pass (MPN CW4055). J–L. P. crystallae sp. nov., Cave Brook, Gouland Downs, Heaphy Track. J. MPN CW3994. K–L. MPN CW3995. M–O. P. rodmorrisi sp. nov., Kahutara Saddle, Seaward Kaikōura Range. M. MPN CW3536. N–O. MPN CW3395. Scale bars = 1 mm.

Fig. 11. Adult female terminalia of cave wētā in the genus Pleioplectron Hutton, 1896. Left column: subgenital plate; central and right columns: ovipositor. A–C. P. gubernator sp. nov. A. Awapoto Hut, Abel Tasman NP (MPN CW4057). B–C. Lewis Pass (MPN CW4071). D–F. P. caudatum sp. nov., Brewster Hut Track, Haast Pass (MPN CW4040). G–I. P. flavicorne sp. nov., Brewster Hut Track, Haast Pass (MPN CW4042). J–L. P. crystallae sp. nov., Cave Brook, Gouland Downs, Heaphy Track. J. MPN CW3993. K–L. MPN CW3990. M–O. P. rodmorrisi sp. nov., Hodder River, Inland Kaikōura Range (MPN CW3822). Scale bars = 1 mm.

Fig. 12. Adult female terminalia of cave wētā in the genus Pleioplectron Hutton, 1896, dorsal view (suranal plate). A. P. simplex Hutton, 1896, Hinewai Reserve, Banks Peninsula (MPN CW4114). B. P. crystallae sp. nov., Salisbury Lodge, Mt Arthur (MPN CW3941). C. P. caudatum sp. nov., Brewster Hut Track, Haast Pass (MPN CW4040). Scale bars = 1 mm.